C++ STL学习——deque

在数据结构中还有一种很常见的队列叫做双端队列，我们在上一篇博客《C++ STL学习——queue》中讲到的队列queue是一种最标准的队列，只能在尾部插入数据，在头部删除数据。而今天我们讲到的deque分别可以在两端进行插入与删除，可以说用起来更加的灵活。

（1）创建一个deque

 

    deque deque1;
    deque deque2(deque1);
    deque deque3(10);
    deque deque4(10,0);

（2）deque尾部插入数据

 

 

    deque1.push_back(1);
    deque1.push_back(2);
    deque1.push_back(3);
    deque1.push_back(4);
    PrintDeque(deque1);

 

（3）deque头部插入数据

 

    deque1.push_front(5);
    deque1.push_front(6);
    PrintDeque(deque1);

（4）查看头部元素、尾部元素和某位置元素

 

 

    cout << "头部元素为：" << deque1.front() << endl;
    cout << "尾部元素为：" << deque1.back() << endl;

    cout << "某位置的元素为：" << deque1.at(2) << endl;
    cout << "某位置的元素为：" << deque1[2] << endl;

 

（5）使用迭代器在某位置插入元素

 

// 使用迭代器插入或删除元素
    deque::iterator iterInsert = deque1.begin();
    iterInsert = iterInsert + 2;
    deque1.insert(iterInsert, 99);
    PrintDeque(deque1);

 

（6）使用迭代器在某位置删除元素

 

    deque::iterator iterErase = deque1.begin();
    iterErase = iterErase + 2;
    deque1.erase(iterErase);
    PrintDeque(deque1);

 

（7）size(), max_size()

 

    cout << "deque1.size = " << deque1.size() << endl;
    cout << "deque1.max_size = " << deque1.max_size() << endl;

 

（8）头部、尾部删除元素

 

 

    deque1.pop_back();
    PrintDeque(deque1);

    deque1.pop_front();
    PrintDeque(deque1);

（9）交换两个deque

 

 

    // 交换两个deque
    deque dequeSwap;
    dequeSwap.push_back(11);
    dequeSwap.push_back(22);
    dequeSwap.push_back(33);

    cout << "deque1:" ;
    PrintDeque(deque1);
    cout << "dequeSwap:";
    PrintDeque(dequeSwap);

    deque1.swap(dequeSwap);
    cout << "deque1:" ;
    PrintDeque(deque1);
    cout << "dequeSwap:";
    PrintDeque(dequeSwap);

 

（10）判断deque是否为空

 

    cout << "deque是否为空：" << deque1.empty() << endl;
    deque1.clear();
    cout << "deque是否为空：" << deque1.empty() << endl;
    PrintDeque(deque1);

 

（11）迭代器打印deque

 

void PrintDeque(deque pDeque)
{
    cout << "deque元素为：";
    deque::iterator dequeIter;
    for (dequeIter = pDeque.begin(); dequeIter != pDeque.end(); dequeIter++)
    {
        cout << *dequeIter << " ";
    }

    cout << endl;
}